If you suffer frequent sinus infections, you might want to talk with your dentist about it. It could be your chronic sinus problems stem from a deeply decayed or infected tooth.

Sinuses are hollow, air-filled spaces in the front of the skull associated with nasal passages. The largest, the maxillary sinuses, are located just behind the cheekbones and above and to the rear of the upper jaw on either side of the face. These sinuses can become painfully congested when infected.

One possible cause for an infection in the maxillary sinus can occur in certain people whose upper back teeth (the molars and premolars) have roots that are close to or even protrude into the sinus. This is normally a minor anatomical feature, unless such a tooth becomes infected.

An infection in teeth with advancing decay or whose nerve tissue has died will eventually reach the root tip through tiny passageways called root canals. If the roots are close to or penetrating the maxillary sinus, the infection could move into the sinus. This is known as Maxillary Sinusitis of Endodontic Origin (MSEO).

A case of MSEO could potentially go on for years with occasional flare-ups of sinus congestion or post-nasal drip. Because of the nature of the infection within the sinus, the affected tooth itself may not show the normal signs of infection like sensitivity or pain. Doctors may attempt to treat the sinus infection with antibiotics, but because the actual source of the infection is within the tooth, this therapy is often ineffective.

If your doctor or dentist suspects MSEO, they may refer you to an endodontist, a specialist in root canals and interior tooth problems. With their advanced diagnostic capabilities, endodontists may have a better chance of accurately diagnosing and locating the source of a tooth-related infection.

As with any non-vital tooth, the likely treatment will be root canal therapy in which the infected tissue within the tooth is removed and the empty spaces filled to prevent future infection. For MSEO, the treatment not only preserves the tooth but may also relieve the infection within the sinus.